Surface-contact railway system.



PATENTED AUG. 4, 1903. W. B. POTTER. SURFACE CONTACT RAILWAY SYSTEM.

APPLICATION FILED APR. 23, 1902.

H0 MODEL.

Inventor William liPotter.

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UNITED STAT S IatentedAugust 4, 1969;.

PATE T OFFICE.

WILLIAM B. POTTER, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GEN- ERAL ELECTRIC COMPANY, A CORPOR-ATION OF NEW YORK.

SURFACE CONTACT. RAILWAY SYSTEM.

SPECIFICATION forming part of LettersPatent No. 735,584, dated August 4, 1903.

Application filed April 23, 1902.

September 7, 1897. Y

The object of my invention is to provide a system of the character shown in the patent above referred to with a metallic returnfeeder so arranged and connected that while substantially all the return-current will be conducted back through it to the generatingstation no substantial difference of potential can exist between it and ground.

My invention consists in providing an electric-railway system with ametallic return feeder, which metallic return is grounded at a point remote or at the end ofthe feeder most distant from the source of energy, but which is elsewhere insulated from the ground.

By the use of a ground connection at the 7 end of the negative feeder farthest from the source of energy the advantages of a metallic return system, such as obviating the requirement of rail-bonding and preventing the electrolytic action on water and gas pipes, which are necessary evils connected with the grounded track-rail return, are obtained, while at the same time the buttons or contacts, which are normally connected with the negative feeder, have their potential main-' tained at the potential of the ground, which eliminates all liability of injury to life and limb from energized negative conductors in the roadway and obviates the necessity of placing switches between the negative studs or conductors and the feeder.

The accompanying drawing shows diagrammatically a surface-contact system embodying the features of my present invention.

In the figure, A A represent the track-rails,

011 which the wheels R R of the car operate.

B, B, B and B are the studs which are Serial No. 104.274. (No model.)

troller-switch s and resistance 'r, and the return from the motor M is connected with the shoe F. The batteryE or auxiliary source of power carried by the car which is used temporarily to pick up the switches when starting the car is connected across the outside shoes F and F and is connected in series with the switch 8 and the resistance r.

The operation of the system is as follows: The switch G is picked up at first by a current which flows from the auxiliary source of power E, carried by the car through the switch 8, resistance 1', shoe F, contact-stud C, actuating-coil of switch G, contact-stud D, shoe F back to the source of power E. When the switch G has been closed in this manner, the switch .9 is opened and the switch G is maintained in its closed position by current from the feeder P flowing through the switch G, contact-stud B, shoe F, resistance 7', motor M, shoe F, contact-stud C, actuatingcoil of switch G, to negative feeder N. As the car moves forward the advance switch G is closed by current from the shoe F flowing through the contact-stud C, actuating-coil of switch G, to negative feeder N, thus energizing the advance stud B and maintaining the contact-stud B energized after the switch G has been opened. The return-feeder N being connected to ground at its farther end, none of the contacts D D, &c., can ever be at a potential substantially different from that of ground, and hence they may be with perfect safety permanently connected to the return-feeder. 7

While I have shown and described a surface-contact system embodying my inven 7 tion, I do not limit myself to such a system,

since my invention would be equally applicable to a sectional third-rail system using a metallic return-circuit and to other wellknown systems.

lVhat I claim as new, and desire to secure by Letters Patent of the United States, is

1. In an electric railway, a source of energy, a positive and a negative feederleading from the same, and a ground connection ata single point, said point being at the end of the negative feeder farthest from the source of energy.

2. In an electric railway, a source of energy, a sectional conductor, switches for connecting the sections of said conductor successively with the said source, an insulated return-conductor, and a single ground connection for said conductor, said ground connection being made at a point remote from the said source of energy.

3. In an electric railway, a source of energy, a positive and a negative feeder connected therewith, a sectional conductor connected to said positive feeder, switches in said connections, a sectional conductor connected with said negative feeder, and a single ground connection for said negative feeder, said ground connection being made at a point remote from the source of energy.

4. In an electric railway, a source of energy, a positive and a negative feeder leading from the same, a sectional conductor connected to said positive feeder through electromagnetic switches, a sectional conductor permanently connected to said negative feeder through the respective coils of said electromagnetic switches, and a single ground connection for said negative feeder, said ground connection being made at a point remote from the source of energy.

5. In a surface-contact system, a source of energy, a positive and a negative feeder leading from the same, a plurality of sectional working conductors, electromagnetic switches for connecting said sectional conductors to said positive feeder, a plurality of sectional switch-energizing conductors independent of said working conductors, electrical connections between said switch-energizing conductors and said negative feeder, and a single ground connection for said negative feeder, said ground connection being made at the end farthest from the source of energy.

6. In a surface-contact railway, a source of energy, a positive and an insulated negative feeder connected therewith, positive sectional conductors, electromagnetic switches for establishin g temporary connection between the positive feeder and the successive positive sectional conductors, each switch provided with a single actuatingcoil, negative sectional conductors, permanent electrical connections each including one of said actuating-coils between said negative feeder and said negative sectional conductors, and contacts making direct connection between the positive feeder and the positive sectional conductors, each switch furnishing current to more than one sectional conductor, and a single ground connection for said negative feeder, said ground connection being made at the end farthest from the source of energy.

In witness whereof I have hereunto set my hand this 21st day of April, 1902.

\VILLIAM B. POTTER.

Vitnesses:

BENJAMIN B. HULL, HELEN ORFORD. 

